首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献，搜索用时 31 毫秒
1.
A type-specific enzyme-linked immunosorbent assay (ELISA) using equine herpesvirus types 1 (EHV-1) and 4 (EHV-4) glycoprotein G was applied for sero-epizootiology of EHV infections in Japan. Recently, an inactivated EHV-1 vaccine has been administered to racehorses for prevention of upper respiratory disease. To examine the effect of the vaccination on the result of the ELISA, 6 horses were experimentally inoculated three times intramuscularly or intranasally with inactivated EHV-1 vaccine. Sera collected from these horses were used to the type-specific ELISA and complement-fixation (CF) test. Although the CF test detected a significant increase of antibody elicited by vaccination, the ELISA did not detect any antibody response. Next, sera collected from thirty-eight horses, which were intramuscularly inoculated with inactivated EHV-1 twice at an interval of four weeks, were used in the ELISA and CF test. The results also indicated that CF titers increased by vaccine inoculation, but ELISA titers did not. To examine epizootiology of EHVs serologically in racehorse populations at two Training Centers of the Japan Racing Association, the type-specific ELISA and CF test were carried out using paired sera collected from racehorses before and after the winter season. The results showed that the ELISA could distinguish EHV-1 and EHV-4 infections in vaccinated horses serologically. In conclusion, the type-specific ELISA is considered to be useful for sero-diagnosis and sero-epizootiological research on EHV-1 and EHV-4 infections not only in unvaccinated horses, but also in vaccinated horses in Japan.  相似文献   

2.
Non-specific hemolysis has often been observed during complement-fixation (CF) tests for equine herpesvirus type-1 (EHV-1), even when the sera have virus-specific CF antibodies. This phenomenon has also been reported in CF tests for various infectious diseases of swine. We found that the sera from 22 of 85 field horses (25.9%) showed non-specific hemolysis during conventional CF testing for EHV-1. Because pretreatment of swine sera with potassium periodate (KIO4) improves the CF test for swine influenza, we applied this method to horse sera. As we expected, horse sera treated with KIO4 did not show non-specific hemolysis in the EHV-1 CF test, and precise determination of titers was achieved.  相似文献   

3.
A single-dilution, sensitive and specific monoclonal antibody-based blocking enzyme-linked immunosorbent assay (B-ELISA) was developed as an alternative to the cumbersome virus neutralization test (VNT) for detection of equine herpesvirus-1 (EHV-1) antibodies. Neutralizing monoclonal antibodies (1H6 and 9C6) raised against EHV-1 (Hisar-90-7 strain) and sera from 70 horses (30 known negative and 40 known positive for EHV-1 antibodies by VNT) were used for standardization of the B-ELISA. Using a single serum dilution of 1:250 in B-ELISA, 100% specificity was obtained with both monoclonal antibodies (Mabs) in comparison to VNT. Similarly, the sensitivity of the B-ELISA was 92.5% and 100% with 1H6 and 9C6 Mabs, respectively. A very high correlation coefficient (r = 0.85) was observed between B-ELISA and VNT that was significant at the p < 0.01 level. B-ELISA detected a more than 3-fold rise in antibody titres in paired serum samples collected from mares aborting owing to EHV-1 infection. Mab 9C6 was chosen for testing 231 field sera from apparently healthy vaccinated and non-vaccinated horses from organized breeding farms belonging to 11 Indian states, and from Bhutan, by B-ELISA and VNT. There was very good agreement between the results obtained by both VNT and B-ELISA (K = 0.9438). Of 231 field sera, 144 samples were negative for EHV- 1 antibodies by both VNT and B-ELISA and 81 were positive by both tests. Two samples negative by VNT were found positive in B-ELISA. On the other hand, four weakly positive samples in VNT (VN antibody titre 0.9 1.2 log10) were negative in B-ELISA. The Mab (9C6)-based B-ELISA was found to be a suitable alternative to VNT for screening large numbers of field sera and enabled confirmatory EHV-1 serodiagnosis.  相似文献   

4.
In this report we examined the presence of specific antibodies against equine herpesvirus type 1 (EHV-1), and equine herpesvirus type 4 (EHV-4) in several equidae, including mules, donkeys, horses. The presence of EHV-1 and EHV-4 in respiratory diseases of equids, and ability of multiplex nested polymerase chain reaction (PCR) screening in simultaneous diagnosis of horses acutely infected by EHV-1 and EHV-4 were also investigated. Sera from 504 horses, mules and donkeys sampled were tested for the presence of EHV-1 and EHV-4 specific antibodies. Blood samples taken from 21 symptomatic horses and nasal swabs taken from 40 symptomatic horses were tested for the presence of EHV-1 and EHV-4 by a multiplex nested PCR. A total of 14.3% (3/21) of buffy coat samples and 32.5% (13/40) nasal swab samples were found to contain EHV-1 DNA, while 19% (4/21) buffy coat samples and 22.5% (9/40) nasal swab samples were found to be positive for EHV-4 DNA. By species, 14.5% of horses, 37.2% of mules and 24.2% of donkeys tested were EHV-1 seropositive. EHV-4 specific antibodies were detected in 237 (81.7%) of 290 horse sera tested. Results from this investigation demonstrate that EHV-1 and EHV-4 are prevalent throughout the equid population, and that donkeys and mules might also represent an important source of infection for other equids. We also showed that the multiplex nested PCR assay might be useful for diagnosis of mixed respiratory infections in horses due to EHV-1 and EHV-4.  相似文献   

5.
Five of 10 pregnant, lactating mares, each with a foal at foot, developed neurological disease. Three of them became recumbent, developed complications and were euthanased; of the two that survived, one aborted an equine herpesvirus type 1 (EHV-1)-positive fetus 68 days after the first signs were observed in the index case and the other gave birth to a healthy foal on day 283 but remained ataxic and incontinent. The diagnosis of EHV-1 myeloencephalitis was supported by postmortem findings, PCR identification of the virus and by serological tests with an EHV-1-specific ELISA. At the time of the index case, the 10 foals all had a heavy mucopurulent nasal discharge, and PCR and the ELISA were used to detect and monitor EHV-1 infection in them. The status of EHV-1 infection in the five in-contact mares was similarly monitored. Sera from three of the affected mares, taken seven days after the index case were negative or had borderline EHV-1-specific antibody titres. In later serum samples there was an increase in the titres of EHV-1-specific antibody in two of the affected mares. In contrast, sera from the five unaffected in-contact mares were all EHV-1-antibody positive when they were first tested seven or 13 days after the index case.  相似文献   

6.
Serological evidence of Equine Herpes virus type 1 (EHV-1) activity in Polo horses in Nigeria is reported for the first time. Eighty-two percent of horses tested with known antigen had precipitating antibodies to EHV-1 while 43% of sera tested against antigen prepared from nasal discharges were positive suggesting that the virus was being excreted in the nasal discharges and probably acting as a source of infection for incontact animals as occurs in on-going acute infections. The result of this study indicates a high prevalence of EHV-1 activity among Polo horses in Nigeria and demonstrates the ubiquitous distribution of the virus in a country that has not been previously investigated.  相似文献   

7.
The gene encoding equine herpesvirus 1 (equine abortion virus; EHV-1) glycoprotein D was engineered into the prokaryotic vector pEX, and expressed as a β-galactosidase fusion product, which was recognized by pooled equine sera and anti-EHV-1 rabbit sera. Antibodies raised against the EHV-1 gD fusion product identified strong bands in infected cells at 66 and 68 K and at 138 K in purified virus, thus characterizing the several forms of this major envelope glycoprotein which is an important candidate for inclusion in subunit vaccines.  相似文献   

8.
A radial immunodiffusion enzyme assay (RIDEA) was developed for detection and quantitation of antibodies to equine herpes virus-1 (EHV-1) in horse sera. The detection and quantitation of EHV-1 antibody levels were based on the diameter of the radial diffusion zone of specific antibody in each serum sample reacting with EHV-1 antigen. The circular zone was made visible using peroxidase-conjugated rabbit anti-horse immunoglobulin G and a substrate containing hydrogen peroxide. The results of the RIDEA were compared with those of virus neutralization (VN) and enzyme-linked immunosorbent assay (ELISA) and found to be highly correlated. The relative sensitivity and specificity (percentage of agreement with VN test) were found to be 98.2 and 92.5%, respectively. Because the test procedure is relatively easy to perform, the RIDEA could be used as a field test to detect antibodies to EHV-1 in horses.  相似文献   

9.
Detection of equine herpesviruses in aborted foetuses by consensus PCR   总被引：1，自引：0，他引：1  
The major role of EHV-1 in equine abortion is widely reported in the literature but the contribution of EHV-2, EHV-3, EHV-4 or EHV-5 remains less well documented. The objective of this study is to evaluate the contribution of these five different EHVs to equine abortion in a variety of biological tissues using a consensus polymerase chain reaction (PCR). The test was validated for specificity and sensitivity in horses before screening specimens from 407 foetuses, stillbirths and premature foals collected over a 2.5-year interval. Positive results obtained with this assay were compared to other EHV type-specific PCR or by sequencing. EHV-1 was identified as the major cause of abortion in French mares (59/407 cases). However, there was evidence to suggest some variation in the potential of EHV-1 strains to induce abortion. Indeed, DNA samples from EHV-2 (in three cases) and EHV-5 (in one case) inferred a role of these viruses in abortion. The presence of viral DNA from EHV-3 or EHV-4 strains was not detected in the specimens studied. The data obtained suggest that the consensus herpesvirus PCR is an efficient screening tool. In association with a specific PCR, the test provides a rapid identification of the type of herpesvirus involved in abortion and is useful for routine diagnostic tests as it allows the identification of herpesviruses other than the EHV-1 strain.  相似文献   

10.
Background: Equine sarcoidosis is a rare, multisystemic, noncaseating, granulomatous and lymphoplasmacytic disease of unknown etiology. A recent report described a horse with granulomatous skin disease displaying histologic, electron microscopic, and polymerase chain reaction (PCR) findings consistent with equine herpesvirus 2 (EHV-2).
Objective: To investigate the presence of EHV-2 and equine herpesvirus 1 (EHV-1) in 8 horses with sarcoidosis.
Animals: Eight horses with sarcoidosis, reported previously.
Methods: Retrospective study. PCR assays of the tissues were performed to detect DNA associated with EHV-1 and EHV-2. For both herpesviruses the target was their respective glycoprotein B gene. Positive controls consisted of DNA from viral cultures of culturettes from naturally occurring respiratory infections of EHV-1 and EHV-2.
Results: The PCR analyses for both equine herpesviruses' DNA were negative in all 8 horses.
Conclusion: The failure to detect DNA from EHV-1 and EHV-2 in paraffin-embedded skin of these 8 horses does not discount EHV-1 or EHV-2 as causing some cases of ES, but lends support to the presumably multifactorial etiologic nature of the disease.  相似文献   

11.
Sero-epidemiological studies conducted between 1995 and 1997 on two large Thoroughbred stud farms in the Hunter Valley of NSW showed clear evidence of EHV-1 infection in foals as young as 30 days of age. Similarly, serological evidence suggested that these foals were infected with EHV-1 from their dams or from other lactating mares in the group, with subsequent foal to foal spread of infection prior to weaning. These studies also provided evidence of EHV-1 infection of foals at and subsequent to weaning, with foal to foal spread of EHV-1 amongst the weanlings. These data indicated that the mare and foal population was a reservoir of EHV-1, from which new cases of infection propagated through the foal population both before and after weaning. The results of these studies support the long standing management practices of separating pregnant mares from other groups of horses to reduce the incidence of EHV-1 abortion. Also, these results have important implications for currently recommended vaccination regimens, as the efficacy of vaccination in already latently infected horses is unknown.  相似文献   

12.
旨在了解新疆地区马疱疹病毒1型感染的流行现状和特点,本研究于2019—2020年从新疆乌鲁木齐、昌吉州、伊犁州、巴州16处规模化马场收集1 657份马血清样品,采用酶联免疫吸附试验（ELISA）进行抗体检测,对不同地区、品种、性别及年龄马匹的马疱疹病毒1型抗体阳性率进行统计分析。结果显示,乌鲁木齐、伊犁州、昌吉州、巴州马疱疹病毒1型抗体阳性率分别为39.34%、22.56%、90.52%、5.00%;纯血马、混血马、哈萨克马、伊犁马、焉耆马、普氏野马的EHV-1抗体阳性率分别为20.34%、32.93%、44.92%、19.35%、5.00%、90.52%;普氏野马与家马的EHV-1抗体阳性率分别为90.52%和29.32%;家马中新疆本土品种马与引进品种马的EHV-1抗体阳性率分别为31.70%和25.50%;母马与公马的EHV-1抗体阳性率分别为38.84%和22.00%;处于幼年、青年、成年、老年阶段的马匹EHV-1抗体阳性率分别为35.37%、33.00%、34.31%、23.81%。结果提示,新疆乌鲁木齐、伊犁州、昌吉州、巴州规模化养殖场普遍存在EHV-1感染,且不同地区、品种、性别及年龄的马EHV-1感染率差异显著（P<0.05）。本研究为新疆地区EHV-1感染的探讨和防控工作提供调查数据。  相似文献   

13.
The prevalence of equine respiratory virus infections among a suspected population of race horses was examined using polymerase chain reaction (PCR). One or more of five equine respiratory viruses were detected in the nasal swabs of 45 of 89 horses (50.6%), and the detection rate of equine herpesvirus type 1 (EHV-1), equine herpesvirus type 4 (EHV-4), equine herpesvirus type 5 (EHV-5), equine rhinitis A virus (ERAV) and equine rhinitis B virus (ERBV) were 5.6%, 7.9%, 39.0%, 2.2%, and 6.7%, respectively. Among the 45 infected horses, 7 were co-infected with EHV and/or equine rhinitisvirus (ERV). Equine influenzavirus and equine arteritisvirus were not detected in any samples. Specific antibodies to EHV-1 and/or EHV-4 were detected in 59 of 73 tested sera (80.8%), using a virus neutralization test. This investigation suggests that equine respiratory viruses are endemic at Seoul Race Park and that the impact of viral infections on race horses’ health in Republic of Korea should be evaluated.  相似文献   

14.
REASONS FOR PERFORMING STUDY: A silent cycle of equine herpesvirus 1 infection has been described following epidemiological studies in unvaccinated mares and foals. In 1997, an inactivated whole virus EHV-1 and EHV-4 vaccine was released commercially in Australia and used on many stud farms. However, it was not known what effect vaccination might have on the cycle of infection of EHV-1. OBJECTIVE: To investigate whether EHV-1 and EHV-4 could be detected in young foals from vaccinated mares. METHODS: Nasal and blood samples were tested by PCR and ELISA after collection from 237 unvaccinated, unweaned foals and vaccinated and nonvaccinated mares during the breeding season of 2000. RESULTS: EHV-1 and EHV-4 DNA was detected in nasal swab samples from foals as young as age 11 days. CONCLUSIONS: These results confirm that EHV-1 and EHV-4 circulate in vaccinated populations of mares and their unweaned, unvaccinated foals. POTENTIAL RELEVANCE: The evidence that the cycle of EHV-1 and EHV-4 infection is continuing and that very young foals are becoming infected should assist stud farms in their management of the threat posed by these viruses.  相似文献   

15.
In this study, IgG subclass responses against equine herpesvirus type 4 (EHV-4) were examined by enzyme-linked immunosorbent assay (ELISA) using a type-specific region of EHV-4 glycoprotein G (gG). ELISA using sera collected from horses experimentally infected with EHV-4 revealed that IgGa and IgGb antibodies were detected at high level, but IgGc and IgG(T) antibody responses were detected at low level or were undetectable. The IgGa antibody response reached its peak on day 10 post-infection, and then dropped. The IgGb antibody response reached its maximum level on day 12 post-infection, and then the level was sustained during at least 28 days after infection. Forty healthy racehorses that had already been infected with EHV-4 possessed antibody against EHV-4. Although IgGa antibodies specific for EHV-4 were not detected in any horses, IgGb antibodies were detected and the levels correlated with total IgG antibodies against EHV-4 gG. The results suggest that EHV-4-specific IgGa and IgGb antibodies are induced in EHV-4-infected horses, and that IgGb antibody, but not IgGa, is long lasting.  相似文献   

16.
  相似文献   

17.
The immunoglobulin G (IgG) subclass response was investigated in horses with or without pyrexia after natural infection with equine herpesvirus type 1 (EHV-1) in the field. All horses were kept at the training centers of the Japan Racing Association and were immunized with an inactivated EHV-1 vaccine before EHV-1 infection. An IgG subclass response dominated by IgGa and IgGb was induced in horses without pyrexia after EHV-1 infection. In contrast, horses that developed pyrexia showed increased IgGc and IgG (T) subclass production in addition to IgGa and IgGb. Although inactivated EHV-1 vaccines are considered to induce a mainly Th-2-biased response, these results indicated that the responses in horses inoculated with inactivated EHV-1 vaccine were not uniform, and that horses with a Th-1-biased response were likely to be protected from pyrexia.  相似文献   

18.
Equine respiratory viral infections cause significant worldwide disease and economic loss. Common causes include equine influenza virus (EIV) and equine herpesviruses-1 and -4 (EHV-1 and -4), and risk of exposure to these agents may be highest in young horses commingling at sales and competitive events. A surveillance study was conducted at two horse shows and two Thoroughbred sales to determine whether horses shed EHV-1, EHV-4, or EIV on arrival, or 2-4 days later, and whether shedding was associated with identifiable risk factors. Real-time polymerase chain reaction assays were used to detect EHV-1, EHV-4, and EIV nucleic acid in nasal swabs obtained from 369 horses at the four events. In response to evidence of clinical disease, 82 additional horses were sampled at two farms providing horses for one of the sales. On arrival at the events, shedding of EHV-1 was detected in 3.3%, EHV-4 in 1.1%, and EIV in 0.8% of horses. EHV-1 was detected at low levels, and EHV-1 and EHV-4 detection was not associated with clinical disease. EIV was detected only in horses at a Thoroughbred sale, in association with an outbreak of respiratory disease traced back to regional farms. On arrival at events, horses younger than 2 years had a significantly greater risk of shedding EHV-1 compared with older horses; no other significant risk factors associated with viral shedding were identified. Thus, there is a risk of exposure to EIV, EHV-1, and EHV-4 at equine events, and horses and events should be managed to mitigate this risk.  相似文献   

19.
A multiplex real-time PCR was designed to detect and differentiate equid herpesvirus 1 (EHV-1) and equid herpesvirus 4 (EHV-4). The PCR targets the glycoprotein B gene of EHV-1 and EHV-4. Primers and probes were specific to each equine herpesvirus type and can be used in monoplex or multiplex PCRs, allowing the differentiation of these two closely related members of the Alphaherpesvirinae. The two probes were minor-groove binding probes (MGB) labelled with 6-carboxy-fluorescein (FAM) and VIC for detection of EHV-1 and EHV-4, respectively. Ten EHV-1 isolates, six EHV-1 positive clinical samples, one EHV-1 reference strain (EHV-1.438/77), three EHV-4 positive clinical samples, two EHV-4 isolates and one EHV-4 reference strain (EHV-4 405/76) were included in this study. EHV-1 isolates, clinical samples and the reference strain reacted in the EHV-1 real-time PCR but not in the EHV-4 real-time PCR and similarly EHV-4 clinical samples, isolates and the reference strain were positive in the EHV-4 real-time PCR but not in the EHV-1 real-time PCR. Other herpesviruses, such as EHV-2, EHV-3 and EHV-5 were all negative when tested using the multiplex real-time PCR. When bacterial pathogens and opportunistic pathogens were tested in the multiplex real-time PCR they did not react with either system. The multiplex PCR was shown to be sensitive and specific and is a useful tool for detection and differentiation of EHV-1 and EHV-4 in a single reaction. A comprehensive equine herpesvirus disease investigation procedure used in our laboratory is also outlined. This procedure describes the combination of alphaherpesvirus multiplex real-time PCR along with existing gel-based PCRs described by other authors.  相似文献   

20.
In vitro interference between equine herpesvirus types 1 and 2   总被引：2，自引：0，他引：2  
Interference between equine herpesvirus types 1 (EHV-1) and 2 (EHV-2) was studied in equine dermis (ED) monolayer cell cultures and equine lymphocyte cultures. Cell cultures were infected with EHV-2, and after a short incubation period, the cultures were superinfected with EHV-1. At various intervals, different measurements of EHV-1 expression in dually infected cultures, compared with those in cultures infected with EHV-1 alone, were studied. In dually infected ED cell cultures, the EHV-1 cytopathic effect, EHV-1 titer, and EHV-1 enzyme-linked immunosorbent assay antigen titer were maximally reduced to values of 40%, 58.5%, and 54.9%, respectively, at postsuperinfection hour (PSIH) 36. Values of these EHV-1 expressions were subsequently increased at PSIH 48. However, thymidine kinase activity was reduced to a maximum of 67.3% reduction at PSIH 48. In dually infected lymphocyte cultures, the EHV-1 titer, EHV-1 infective centers, EHV-1 enzyme-linked immunosorbent assay antigen titer, and thymidine kinase activity were maximally reduced to values of 77.4%, 78.7%, 98.3%, and 72.9%, respectively, at PSIH 24. These reductions of EHV-1 expressions were completely abrogated at PSIH 48 to 72. In both cell culture systems, a marked interference of EHV-1 by EHV-2 was observed; this was transient in the lymphocyte cultures, but was more prolonged in ED cell cultures. This interference appeared not to be interferon mediated. The multiplication of EHV-2 in the dually infected ED cell cultures appeared unaffected.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号